Modular sample conditioning system

ABSTRACT

An in-stream sample collection and conditioning system which is easier to implement and maintain, more cost effective, and more reliable than existing systems. The preferred embodiment of the present system contemplates a modular system adaptable to a variety of diverse configurations and criteria, the system having incorporated therein a base piece formed of interconnecting modular base members, the base piece having fluid passageways formed therein to provide fluid flow between the adjacent base member. Situated adjacent to each of the modular base members forming the base piece are modular conditioning components, each selected from a field of diverse conditioning types and configurations, and adapted for the contemplated use. The present invention further contemplates a unique and useful system for joining the various modular components forming the present system, in a manner which provides redundant leak resistance, flexibility in forming various conditioning requirements and adaptability to diverse existing sampling stream interfaces, as well as a new and unique method for attachment of the transport tube to the device body. Lastly, the preferred embodiment of the present invention contemplates a highly precise, low tolerance juxtaposition of the various components forming the present system, utilizing an extremely thin sheet, formed membrane/gasket member, implemented in such a manner as to provide high thermocycling characteristics as well as high pressure tolerance, coupled with a low failure/leakage rate.

TECHNICAL FIELD OF THE INVENTION

This invention relates to the analysis of fluids in a fluid processstream, such as implemented by petrochemical plants, refineries, gasseparation plants, etc., and in particular to an in-stream samplecollection and conditioning system which is easier to implement andmaintain, more cost effective, and more reliable than existing systems.

The preferred embodiment of the present system contemplates a modularsystem adaptable to a variety of diverse configurations and criteria,the system having incorporated therein a base piece formed ofinterconnecting modular base members, the base piece having fluidpassageways formed therein to provide fluid flow between the adjacentbase member(s).

Situated adjacent to each of the modular base members forming the basepiece are modular conditioning components, each selected from a field ofdiverse conditioning types and configurations, and adapted for thecontemplated use, the system dispensing with the necessity of tubes,pipes, and traditional fittings. The present system as a whole providesa wholly new and unprecedented system for custom building fluid streamsampling and conditioning systems with heretofore unavailable"off-the-shelf" components.

The present invention further contemplates a unique and useful systemfor joining the various modular components forming the present system,in a manner which provides redundant leak resistance, flexibility inproviding various conditioning configurations, and adaptability todiverse existing sampling stream interfaces.

Lastly, the preferred embodiment of the present invention contemplates ahighly precise, low tolerance juxtaposition of the various componentsforming the present system, utilizing an extremely thin sheet formedmembrane/gasket member, implemented in such a manner as to provide highthermocycling characteristics as well as high pressure tolerance,coupled with a low failure/leakage rate.

BACKGROUND AND PRIOR ART OF THE INVENTION

While the prior art has contemplated various and diverse systems forsampling and/or conditioning fluids in a process stream, said prior artsystems tended to require a "custom" configuration for each site,entailing an expensive and time-consuming design, fabrication, andinstallation.

BACKGROUND

Overview of Sample Conditioning Systems

Processes as implemented in, for example, petrochemical plants,refineries, gas separation plants, etc. frequently require "on stream"analysis of process fluids, which are performed by analyzers locatednear the fluid sample source. Sample fluids flow directly from thesource to the analyzer through an arrangement of piping and specialtycomponents. This arrangement, referred to as a "sample conditioningsystem", is configured to extract fluid sample from the source,transport it to the analyzer; and, in the process, condition the fluidso that it is compatible with the analyzer.

Conditioning of the sample fluid by the sample conditioning system mayconsist of, for example:

(1) filtration to remove unwanted solids or liquids

(2) coalescing to remove aerosol droplets of liquids

(3) heating to prevent condensation of vapor

(4) flow and pressure control and measurement

(5) cooling to lower the sample dew point or remove unwanted liquidvapor.

The sample conditioning system may perform additional functions such asselection of one of several fluid streams for analysis by a singleanalyzer. This is called "stream selection" or stream multiplexing.

All of the components utilized for extracting, transporting, andconditioning the sample, as described previously, are part of the sampleconditioning system. Some sample conditioning systems have componentsdistributed along the entire distance between the source and theanalyzer. Typically the largest concentration of these sampleconditioning system components are located close together.

Reference to sample conditioning systems in the present invention aredesigned primarily for utilization in conjunction with closely groupedcomponent arrangements, although the present system does includeinnovative features which could be useful for more spaced componentarrangements. The components as implemented in the sample conditioningsystem, which are utilized for conditioning sample fluids, willhereinafter be referred to as conditioning components.

Current Construction of Sample Conditioning System

Current construction methods for Sample Conditioning System vary littlefrom their first appearance several decades ago. Conditioning componentsare typically mounted on a vertical panel or shallow enclosure and areinterconnected by tubing, piping, and fittings. Heavier conditioningcomponents are mounted to the plate or enclosure with brackets whilelighter conditioning components are supported by interconnectingfittings, piping, tubing, etc. Some Sample Conditioning System arefurther protected by "analyzer houses" or shelters which are usuallylarge enough for maintenance technicians to work in and may also houseprocess analyzers. Common to all of the above configurations is the factthat most Sample Conditioning Systems include a uniquely designed andimplemented conduit system for conveying the fluid from the samplestream, and through the components, sometimes resulting in a maze ofconduits, thereby resulting in high cost, maintenance, and thepropensity for leakage from the system.

Problems Associated With Current Construction Methods

Several problems arise from the use of current construction methods.Some of the major problems are as follows:

(1) Excessive Size

Sample Conditioning System produced by current construction methodsrequire much space--a commodity which is very valuable in process areas.In general, lowering the size of analyzer houses or Sample ConditioningSystem enclosures results in significant cost reduction due to the highcost for space in process areas.

(2) Labor Intensive

Configuring, mounting and interconnecting of conditioning componentsduring the construction of a Sample Conditioning System is very laborintensive and therefore costly.

(3) Excessive Sample Conditioning System Internal Fluid Volume andStatic Fluid Pocket Volume

It is well known in the industry that large internal volumes and staticfluid pocket volume have a negative influence on the performance ofSample Conditioning System. The larger the internal volume and/or staticfluid pocket volume in a Sample Conditioning System and the longer ittakes to sweep it our after a sample fluid composition change occurs.Therefore Sample Conditioning System with large internal and/staticfluid pocket volume require larger amounts of fluid to sweep, resultingin significant inefficiency.

In most cases it is desirable for fluid sample composition arriving atan analyzer to track closely the composition of the sample fluid at itssource. In many instances the sample fluid utilized for sweeping cannotbe returned to the source and therefore must be wasted. Thereforereducing the internal and static fluid cost related to loss of samplefluid and its environmentally safe disposition. Tube and pipeinterconnections between conditioning components contribute the bulk ofa Sample Conditioning System's internal volume. Fittings, especiallypipe fittings, introduce static fluid pocket volume to the SampleConditioning System.

(4) Safety and Environmental Concerns

It is common for sample fluid leaks to occur in conditioning componenttubing and pipe interconnections and as a result of conditioningcomponent failures. Examples of common conditioning component failuresare: pressure regulator diaphragm ruptures and valve stem packingshrinkage due to wear or temperature changes. When fluid leaks occur,maintenance technicians can be exposed to toxic materials and fire orexplosion hazard. Fluid used for continuously sweeping a SampleConditioning System presents disposal problems and increases operationalexpenses.

PRIOR ART

While the prior art may have contemplated in some degree the utilizationof block components having fluid passageways therethrough for fluidconditioning and/or conveyance, said prior art known to the inventor hasbeen limited to hydraulics and other distinguishable configurations andapplications.

For example, U.S. Pat. No. 3,831,953, issued 1974 to Leibfritz et alcontemplates a "Solenoid Operated Valve Assembly", teaching a "sealingunit adapted to be clamped between parallel faces of mating valve parts,comprising a sheet-like resilient gasket member engaged with one of saidfaces, and a uniform thickness plate member engaged with the other ofsaid faces, said gasket member having apertures bounded one side only bylateral rib means which extend beyond the thickness thereof so that saidgasket member is squeezed at the rib means between said parallel faces.

While the '953 device may contemplate a redundant leak isolating system(see col 5, lines 528, for example), the system fails to contemplate theoverall method and apparatus of the present invention, as pertaining tomodular sampling components. The system is clearly designed as valveassembly in a hydraulic system, and as such would not be able to beutilized in the present invention. Other differences between '953 andthe present invention will be made clear in the discussion followinginfra.

GENERAL SUMMARY DISCUSSION OF THE INVENTION

Unlike the prior art, the present invention provides a cost effective,relatively easily implemented, reliable, and efficient system forin-stream sampling, adaptable to a variety of configurations andconditions.

The invention includes a method for:

(a) Constructing a sample fluid conditioning system utilizing modularbase and modular conditioning components. This method eliminates tubeand pipe interconnections and fittings. This reduces static fluid pocketvolume and internal system volume, reduces mounting space requirements,and decreases the time and skill required to construct a sampleconditioning system. It also decreases the time required for replacementof failed conditioning components.

(b) Constructing base and conditioning modules. The method furtherreduces internal and static fluid pocket volume of sample conditioningsystems fabricated from modules constructed by this method. This methodalso provides a means for capturing and transporting to an externaldisposal system any sample fluids which would otherwise leak to thesample conditioning modules external environment as a result of fluidbreaching a fluid barrier or failure of a conditioning component.

(c) Constructing fluid barriers between two surfaces. This methodprovides a means for leak-free communication of fluids betweenpassageways of adjoining base and conditioning modules and also betweenpassageways of adjoining base modules. This method of constructing fluidbarriers also accommodates the capturing of leaks across a primary fluidbarrier to prevent fugitive emission of sample fluid. The fluid barriersconstructed by this method remain leak free even after thermo-cycling.

(d) Compressing fluid barrier material between two surfaces utilizingstrain in a threaded member for supplying the required compressiveforce. This method compensates for displacement in the seal barriermaterial which would otherwise reduce the compressive force and permitfluid leaks.

(e) Retaining fluid barrier material utilizing beveled surfaces. Thismethod permits the use of thin plastic or elastic fluid barriermaterials and is less susceptible to displacement when thermo1 cycled.

(f) Mounting modular base and modular conditioning components in amanner which provides the clamping force required for sealing of fluids.

(g) Attaching fluid transport tube to a base module in a manner thatprevents sample fluid leaks to the surrounding environment in the eventof a primary fluid barrier failure.

It is therefore an object of the present invention to provide a modularsystem for in-stream sampling of a fluid in a fluid sampling stream.

It is another object of the present invention to provide an in-streamsampling system which may be utilized in conjunction with a variety ofsystem configurations and requirements, without the need for customfluid conveyance means, such as piping, conduits or the like.

It is still another object of the present invention to provide a systemfor in-stream sampling, comprising a modular base member adapted to havesituated thereupon, in fluid impermeable fashion, a diverse assortmentof communicating fluid conditioning modules.

It is still another object of the present invention to provide aredundant leak sealing means to prevent fugitive emissions.

It is still another object of the present invention to provide anultra-thin gasket sealing system configured to provide highthermocycling tolerances, and perform satisfactorily in a broad range oftemperature extremes.

Lastly, it is an object of the present invention to provide anultra-thin gasket sealing system configured to provide an effective, lowmaintenance, high-pressure seal.

BRIEF DESCRIPTION OF DRAWINGS

For a further understanding of the nature and objects of the presentinvention, reference should be had to the following detaileddescription, taken in conjunction with the accompanying drawings, inwhich like parts are given like reference numerals, and wherein:

FIG. 1 illustrates an isometric view of a component conditioning modulemounted to a base module. The internal passages, fluid barrier materialand valve are shown. Grooved passages on the module surfaces are notshown.

FIG. 2 illustrates a side view of a plurality of conditioning componentmodules mounted to base modules, assembled side by side with fluidbarrier material between adjacent modules.

FIG. 3 provides a schematic flow diagram of a typical sampleconditioning system.

FIG. 4 consists of a cross sectional view taken along line I,I ofFIG. 1. This view includes a cross sectional view of an adjacent basemodule and collection passage grooves not shown in FIG. 1.

FIG. 4A provides a detail of the junction where the conditioningcomponent module and base module contact the fluid barrier. This viewshows the surface segments of each module in contact with the fluidbarrier.

FIGS. 4B and 4C sets forth details showing where passages from twomodules in conjunction with surface segments and fluid barrier segmentsform a sealed passage junction.

FIG. 5 provides a cross sectional view taken along line II,II of FIG. 1.This view includes a cross sectional view of passages and grooves.

FIG. 5A illustrates a detail of the junction where conditioningcomponent module and base module contact the fluid barrier. This viewshows the surface segments of each module in contact with the fluidbarrier.

FIG. 5B is a figure showing in detail where passages from two modules,in conjunction with surface segments and fluid barrier segments, form asealed passage junction.

FIG. 6 is a cross sectional top view of a plurality of conditioningcomponent modules and base modules showing horizontal passages for fluidcommunication between the base module and conditioning component module.This arrangement performs the functions illustrated in FIG. 3.

FIG. 7 is a cross sectional view taken along line I,I of FIG. 1including an adjacent base module not shown in FIG. 1. This view doesnot include collection grooves shown in FIG. 4 and demonstrates howfluid can teak to the surrounding atmosphere.

FIG. 8 provides an exploded isometric view of a conditioning componentmodule, fluid barrier material and base module. The grooved surfaces,passage openings, and fluid barrier openings are shown, passages and theinternal portion of the valve are not shown.

FIG. 9 is an assembled isometric view of FIG. 8 including the exteriorview of the bolts which hold the assembly together.

FIG. 10 is a view of the invention of FIG. 5, showing a cross section ofthe assembly bolts, mounting rail, mounting surface, and screwsretaining assembly to the mounting surface.

FIG. 11 is a modification of FIG. 4A showing a depression in thesurfaces of the conditioning component module and base module for thepurpose of reducing contact area with the fluid barrier material.

FIG. 12 sets forth a modification of FIG. 10 showing how bolt length canbe increased by using spacers. Increasing bolt length increases thetotal bolt strain and its capability to compensate for fluid barrierdisplacement.

FIG. 13 is a modification of FIG. 11, showing a sloped segment in thesurface depression in both modules for the purpose of forming a wedgefluid barrier. The modules surfaces are shown in contact with the fluidbarrier material without a clamping force applied.

FIG. 14 further illustrates the invention of FIG. 13, after a clampingforce has been applied causing the sloped surface segments to displacefluid barrier material thereby forming a wedge shaped fluid barrierwhich resists blowout.

FIG. 15 provides a composite of FIG. 4A and FIG. 14, showing a slopedsegment in the surface of the conditioning component module and a flatsegment in the surface of the base module. This illustrates a half wedgeshaped fluid barrier.

FIG. 16 sets forth the invention of FIG. 14, modified to show the slopedsurfaces of both modules in contact as a result of applied clampingforce, sloped surface depth, and fluid barrier thickness acting inconcert.

FIG. 17 provides an isometric view of two base module with fluid barrierinserted between showing only horizontal passages, and openings in thefluid barrier material. Vertical passages and conditioning componentmodules are not shown. This FIG. illustrates how adjacent base modulescan be joined, and rendered leak free to the surrounding environment ina manner similar to the method utilized for achieving the same resultswith conditioning component modules and base modules.

FIG. 18 is a cross sectional view of a typical male pipe threadinglyengaged in a body containing female pipe threads. This view illustrateshow cavities in this arrangement can trap fluids.

FIG. 19 provides an exploded isometric view of a mounting rail and pins.

FIG. 20 illustrates an isometric, assembled view of three base modulesand two termination modules on a mounting rail.

FIG. 21 sets forth an isometric view of the three base modules of FIG.20 showing grooves in the modules which mate with the mounting rail.

FIG. 22A is an isometric cross sectional exploded view of a nut, twoferrules, a length of tubing and a threaded module segment.

FIG. 22B provides an isometric cross sectional assembled view of FIG.22A showing passages and cavities.

DETAILED DESCRIPTION OF THE INVENTION

The preferred embodiment of the present invention includes a novelmethod for constructing sample conditioning systems. Said methodsimplifies construction, reduces construction time, improvesperformance, is safer to operate and maintain and essentially eliminatesfugitive sample fluid emissions to the environment. In this method,conditioning components such as valves, pressure regulators, flowmetersand filters are constructed in a modular fashion.

The conditioning component modules are mounted to a modular base, asshown in the block having conduits formed therein in FIG. 1. In FIG. 1,the conditioning component module 11, shown, is designed to perform avalve function, and is shown mounted to base module 12. The presentinvention provides for essentially all types of conditioning componentsto be made modular and mounted to base modules such as (12), above, andis not limited to the conditioning component having a valving functionas illustrated in FIG. 1.

Base modules with mounted conditioning modules are then arranged in aside by side fashion as shown in side view FIG. 2. In FIG. 2, basemodules 57, 58, 59, 60, 61, 62, and 63 can be seen in a side by sidearrangement with mounted conditioning components 64, 65, 66, 67, 68, 69and 70. A means, not shown in FIG. 2, retains the modules in their sideby side orientation and provides for mounting of the entire moduleassembly. Internal passages in conditioning component modules and basemodules conduct sample fluid through the network of conditioningcomponents in accordance to predetermined fluid flow requirements.Novel-fluid barrier means between base modules and between base modulesand component modules prevent undesired fluid flow between internalpassages and also prevent fluid leaks to the environment.

Fluid passes directly from a passage in one module to a passage inanother module without the need for interconnecting pipes, tubing orfittings, via the base member, which conveys the fluid via conduitsformed therein to adjacent conditioning modules, which mount upon thebase at aligned, predesignated conduit coordinates. Because there is noneed for excessive piping, the present system provides an efficiencywhich aids in simplifying the construction task, reduces overall cost,and significantly improves function by eliminating static fluid pocketvolume and reduces sample conditioning systems internal volume.

Prior art methods of construction relate primarily to pneumatic andhydraulic fluid control modules, such as shown in U.S. Pat. No.3,831,953, discussed infra while the preferred embodiment of the presentinvention addresses problems associated with sample fluid conditioningfor analysis by automated analyzers. The needs are very different. Forexample, of prime importance in sample fluid conditioning is the needfor minimal internal system volume, and the absence of static fluidpocket volume. This is not a requirement in typical pneumatic orhydraulic fluid control devices. Another example is the need in samplefluid conditioning systems for minimizing or eliminating fugitive fluidemissions resulting from fluid leaks which also is not a usualrequirement for pneumatic or hydraulic fluid control devices.

The method of utilizing conditioning component modules and base modulesin the particular manner hereafter described allows conditioningcomponent modules to be designed and constructed without compromise withregard to the need for fluid communication between and among otherconditioning component modules. With this method, internal fluidpassages in conditioning components modules need only mate at any pointalong appropriate horizontal passages in the base modules. Thesehorizontal fluid passages in all of the base modules may be standardizedwith regard to location of the openings which communicate sample fluidto adjacent base modules. The task of designing passages in conditioningcomponent modules to mate with horizontal passages in the base module issubstantially easier than designing conditioning component modules whichintercommunicate, without use of base modules, with adjacentconditioning component modules.

Schematic Flow Diagram

Prior to constructing a sample conditioning system utilizing componentconditioning modules and base modules, one must first establish aschematic flow diagram. An example of such a diagram, as seen in FIG. 3,must include the conditioning components, such as valves 1, 2, and 3;filter 4, flow meters 5, and 6; and pressure regulator 7, which will berequired to provide the desired sample fluid conditioning for aspecific, exemplary application. The fluid communication circuitsbetween conditioning components should also be indicated by theschematic flow diagram. In the schematic flow diagram of FIG. 3 thereare three fluid circuits. The first fluid circuit is comprised ofpassage 8 valve 1 and passage 39. The second fluid circuit is comprisedof a portion of filter 4 which includes filter element 45, passage 10,pressure regulator 7, passage 40, valve 2, passage 41, flowmeter 5, andpassage 42. The third fluid circuit consist of a portion of filter 4,passage 9, valve 3, passage 43, flowmeter 6 and passage 44.

It should be noted that the schematic flow diagram of FIG. 3 is anexample of a typical sample conditioning system. However, the inventionapplies to all types of sample conditioning system some of which maybesubstantially more complex and include conditioning components not shownin FIG. 3.

In normal operation of the sample conditioning system of FIG. 3, samplefluid enters at entrance 46 of passage 8 then flows through the firstfluid circuit. The first fluid circuit flow then branches into thesecond and third fluid circuits upon entering filter 4. Fluid exits thesecond fluid circuit from passage 42 into an analyzer not shown. Fluidexits the third fluid circuit from passage 44 to a safe disposal systemnot shown. The fluid flow rate through the first fluid circuit is equalto the sum of the fluid flow rates of the second and third fluidcircuits. The purpose of the second fluid circuit is to condition samplefluid so that it is compatible with a given analyzer. In this particularcase the fluid is filtered by filter element 45, fluid pressure iscontrolled by pressure regulator 7, fluid flow rate is controlled byvalve 2, and flow rate is monitored by flowmeter 5. Passages 10,40,41,and 42 provide fluid interconnections between conditioning components.

The amount of time required for sample fluid to be transported from asource to an analyzer is commonly referred to as the system lag time.The system lag time represents the minimum time required for an analyzerto respond to a composition change at the sample fluid source. Fluidflow rate through the sample conditioning system has a direct impact onsystem lag time.

The purpose of the third fluid circuit is to aid in adjusting the totalfluid flow rate in the first fluid circuit. Altering the flow rate ofthe third fluid circuit using valve 3 changes the fluid flow rate of thefirst fluid circuit and subsequently impacts the system lag time. Thefluid circuit arrangements and conditioning components which can beincluded in a sample conditioning system are not limited to thosereferenced in FIG. 3. The schematic flow diagram established need not betangible. A mental, computer generated, or any other means forestablishing a schematic flow diagram containing the aforementionedinformation will suffice. The purpose for the schematic flow diagram isto aid in the selection of component conditioning modules and basemodules which will be utilized in the construction of a modular sampleconditioning system.

Mounting a Conditioning Component Module to a Base Module and theResulting Typical Fluid Flow Paths

After a schematic flow diagram has been established the requiredcomponent conditioning modules, which have been designed to performspecific sample fluid conditioning functions, are mounted to theirrespective base modules. An example of this is seen in FIG. 4 where acomponent conditioning module 11, designed to perform a fluid meteringvalve function, is mounted to base module 12. Base modules arespecifically designed to provide the fluid communication with thecomponent conditioning module to which it is mated and otherconditioning component modules and base modules. Base modules alsoprovide fluid communication between other base modules and componentconditioning modules. In the example shown in FIG. 4 it can be seen thatsample fluid 122 entering base module 12 at passage opening 20, flowsthrough passage 13, passage 14, passage opening 21, opening 28 in fluidbarrier material 30, enter component conditioning module 11, at passageopening 22, flow through vertical passage 15, horizontal passage 16,valve cavity 31, vertical passage 17, exit the component conditioningmodule 11 at the passage opening 23, flow through opening 29 in sealbarrier material 30, re-enter base module 12 at passage opening 24, flowthrough vertical passage 18, horizontal passage 19, exit base module 12at passage opening 33 and enter adjacent base module 12A.

The metering valve 25 comprised of valve stem 27, stem tip 32, and valveseat 26 operates in a conventional manner, thus by rotating valve stem27 the action of male thread 38A and female thread 38B causes the stemtip 32 to change its position relative to valve seat 26 which in turnalters the resistance to fluid flowing through valve cavity 31. FIG. 4illustrates how sample fluid flows through a typical componentconditioning module and base module combination.

From this example it can be clearly seen that it is possible to mountmany different types of component conditioning modules to base modules,and that in a similar manner sample fluid can be transported from afirst passageway opening in the base module, through internal passagesof the base module, into a component conditioning module for the purposeof performing a specific sample fluid conditioning function, re-enterthe base module exit through a second passage opening in the base moduleand thereon flow into an adjacent base module.

Containment of Fluid Leaks Across a Primary Fluid Barrier

Many conditioning components designed by prior art methods aresusceptible to leakage of fluids to the environment which is generallyreferred to as fugitive emissions. Typical sources of fluid leaks inconditioning components are damaged static fluid barriers, dynamic fluidbarriers, and fluid containment barriers such as diaphragms in pressureregulators. Other common sources of fluid leaks to the environment inprior art are threaded pipe and tube interconnecting fittings. Theinvention prevents fluid leaks of all sources from entering theenvironment. It accomplishes this by capturing the leaking fluid andtransporting it to an external site. FIG. 5 illustrates how, in the caseof a dynamic fluid barrier failure, leaking fluid 187 is captured andtransported to the base module 12's fluid containment passage 47.

Under normal operation lower stem fluid barrier 56 prevents sample fluid122 from entering the fluid containment network of base module 12 andcomponent conditioning module 11 which is comprised of cavity 54,passages 53, 52,48, and 47. Upper stem fluid barrier 55 is a barrierbetween the external environment and cavity 54.

In the event of a lower stem fluid barrier 56 failure, sample fluid 122enters cavity 54, flows through horizontal passage 53, vertical passage52 and vertical passage 48 into horizontal passage 47 where it issubsequently transported, by way of the sample conditioning system'sfluid containment network to an external disposal site. Upper stem fluidbarrier 55 prevents sample fluid 122 in cavity 54 from leaking to theexternal environment. The Sample Conditioning System's fluid containmentnetwork is comprised of horizontal passages 47 and correspondingpassages in other base modules of the Sample Conditioning System. Whenbase module with mounted conditioning component modules are assembledside by side as shown in FIG. 6, the vent collection passage of eachbase module mechanically align and are in fluid communication.

Together fluid containment passages 47, 70, 71, 72, 73, 74, and 75 ofassembled base modules comprise the Sample Conditioning System's fluidcontainment network 76. When Sample Conditioning System's fluidcontainment network 76 is in fluid communication with an externaldisposal site not shown, sample fluid 187 captured in any of theconditioning component module and base modules fluid containmentnetworks will be transported and vented to the external disposal site.

The fluid containment network of a conditioning component module andbase module mating combination may collect sample fluid leaks from aplurality of sources. In all such cases however, the captured leakingfluid will be transported to the conditioning component module and basemodule's fluid containment passage where it will ultimately be vented tothe external disposal site by way of the Sample Conditioning Systemfluid containment network 76.

It should be noted that the Sample Conditioning System's fluidcontainment network 76 is normally maintained at a pressure lower thanthe sample fluid pressure in conditioning component module and basemodule. Typically the fluid containment network 76 pressure is within 5PSI of atmospheric pressure. The differential pressure across upper stemfluid barrier 55 being typically less than 5 PSI reduces the risk ofsample fluid breaching this fluid barrier.

In order for sample fluid to leak to the atmosphere, lower stem fluidbarrier 56 and upper stem fluid barrier 55 would have to failsimultaneously. If in some cases sample fluid leaking to the atmospherepresents an excessive hazard, then the Sample Conditioning System fluidcontainment network 76 should be maintained at sub atmospheric pressure.This will insure that if upper stem fluid barrier 55 is damaged samplefluid will not flow to the atmosphere, instead, gas from the surroundingenvironment will flow into the Sample Conditioning System fluidcontainment network. In a similar manner other types of dynamic fluidbarriers and static fluid barriers can be prevented from leaking samplefluids to the environment when a fluid barrier failure occurs.

The junction where two passage openings, located on separateconditioning components module's or base modules, are in fluidcommunication are called passage junctions. A typical passage junction95 is seen in FIG. 5. Passage opening 49, fluid barrier opening 50, andpassage opening 51 in combination comprise passage junction 95. Passagejunctions must be sealed to prevent sample fluid from leaking to theexternal environment or into other passage junctions.

It can be seen in FIG. 7 that without special provisions fluid 122contained in passages of may be and base modules 12 and 12A can leakfrom a passage junction into the environment; such as is seen at 77a,77b, and 77c; or into other passage junctions as seen at 78a, and 78b.From FIG. 7 it can also be seen that fluid leaks could occur on bothsides of fluid barrier material 30 if precautions were not otherwisetaken.

Therefore the method of sealing to prevent fluid leaks from occurring atpassage junctions must protect against fluid leaks which could arise oneither or both sides of seal barrier material 30. The invention includesa special method for sealing around passage junctions which are betweenconditioning component module and base module and also passage junctionwhich are between two adjacent base module's. The passage junctionsealing method of the invention provides two series fluid barriersseparated by a collection passage on both sides of fluid barriermaterial 30.

The following method describes the preferred embodiment for constructionof a static fluid barrier between a conditioning component module and abase module such method providing, on both sides of the fluid barriermaterial, two series seal separated by a collection passage in fluidcommunication with an external disposal site.

Referring to FIGS. 8, 9, and 10, the method consists of the following:

A first passage groove 81 (FIG. 8) is formed in the surface 91 of basemodule 12 surrounding passage openings 21 and 24 and intersectingpassage opening 49.

A second passage groove 82 is formed which intersects opposite sides ofpassage groove 81, and passes between passage openings 21 and 24.Passage grooves 81 and 82 are formed in a manner that will provide aspace 86 surrounding passage opening 24; a space 85 surrounding passageopening 21; and a space 87 surrounding passage groove 81.

A third passage groove 83 is formed in the under surface 92 ofconditioning component module 11 surrounding passage openings 22 and 23and intersecting passage opening 51.

A forth passage groove 84 is formed which intersects opposite sides ofpassage groove 83 and passes between passage openings 22 and 23, passagegrooves 83 and 84 are formed in a manner that will provide a space 90surrounding passage openings 23, a space 89 surrounding passage openings22; and a space 88 surrounding passage groove 83.

Conditioning component module 11 is then mounted to base module 12 (FIG.9 and 10). When mounted as shown in FIG. 9, passage grooves 83 and 84 inconditioning component module 11 are in approximate alignment and havethe same approximate shape and geometry as passage 81 and 82 of basemodule 12, In the preferred embodiment a fluid barrier material 30 isinserted between conditioning component module 11 and base module 12,Bolts 34 and 35 secure the alignment between conditioning component 11and base module 12. Other fastening means may be used for this purpose.Openings 28 (FIGS. 4, 5, 8, and 9) in the fluid barrier allows fluid toflow between passages 14 and 15; opening 29 allows fluid to flow betweenpassages 17 and 18; and opening 50 (FIG. 5) allows fluid to flow betweenpassages 48 and 52.

By tightening bolts 34 and 35 (FIG. 10) conditioning component module 11and base module 12 apply a force to opposite sides of fluid barriermaterial 30. The first fluid barrier 96 (FIGS. 4, 4A, 4B, 4C, 5, and 8)around the passage opening junction 93; comprised of passage openings21, fluid barrier opening 28 and passage opening 22; is formed by space85 on base module 12, space 89 on conditioning component module 11 andthe segment 103 of fluid barrier 30 which is sandwiched directly betweenspace 85 and 89. The first fluid barrier 96 is surrounded by segments ofgroove 81 and groove 82 on base module 12 and grooves 83 and 84 onconditioning component module 11.

The second fluid barrier 97 around passage opening junction 93 is formedby space 86, 87, 88, and 90 and the segment of fluid barrier 104material sandwiched directly between spaces 86 and 90; and segment offluid barrier material 105 between space 87 and 88. Passage grooves 81,82, 83, and 84, in combination, surround passage opening junction 93 onboth sides of fluid barrier 30, in a manner that divides the first fluidbarrier 96 and second fluid barrier 97 of passage opening junction 93.In the event that sample fluid breaches the first fluid barrier 96encircling passage opening junction 93, on either or both sides of fluidbarrier 30, passage grooves 81, 82, 83, and 84 will capture the fluidand transport it to passage junction 95; comprised of passage opening49, passage opening 51, and fluid barrier opening 50; into passage 48then into horizontal passage 47 where it will be subsequently vented toan external disposal site as previously described. The second fluidbarrier 97 in the event of a leak contains fluid within the passagegrooves 81, 82, 83, and 84 preventing it from leaking to the surroundingenvironment or into adjacent passage junction 94.

The first fluid barrier 98 around passage junction 94; comprised ofpassage opening 24, fluid barrier opening 29, and passage opening 23, isformed by space 86 on base module 12, space 90 on conditioning componentmodule 11, and the segment 104 of fluid barrier 30 which is sandwicheddirectly between space 86 and 90.

The second fluid barrier 99 around passage junction 94 is formed byspace 85, 87, 88, and 89 and the segment of fluid barrier 105 sandwichedbetween space 88 and 87; and segment of fluid barrier 103 sandwichedbetween space 85 and 89. Passage grooves 81, 82, 83, and 84 incombination surround passage opening junction 94, on both sides of fluidbarrier 30 in a manner that divides the first fluid barrier 98 andsecond fluid barrier 99 of passage opening junction 94.

In the event that sample fluid breaches the first fluid barrier 98encircling passage opening junction 94, on either or both sides of fluidbarrier 30, passage grooves 81, 82, 83, and 84 will capture the fluidand transport it to passage junction 95, into passage 48, then intohorizontal passage 47 where it will be subsequently vented to anexternal disposal site as previously described.

As an alternate means, collection passage grooves may be formed in thefluid barrier material in special cases. However, in the preferredembodiment collection passage groves are formed on the surface of theconditioning component module and base module as previously described.Fluid barrier 100 prevents fluid communication between the externalenvironment and passage junction 95; and between the externalenvironment and groove 81 and 83. Passage junction 95 is comprised ofpassage opening 49, fluid barrier opening 50, and passage opening 51.Fluid barrier 100, is formed by space 87 on base module 12, space 88 onconditioning component module 11, and the segment 105 of fluid barriermaterial 30 which is sandwiched between space 87 and space 88. Sealbarrier segment 105, when conditioning component module 11 is mounted tobase module 12 and fluid barrier material 30 is inserted between,surrounds passage groove 83 of the conditioning component module 11,passage groove 81 of base module 12, and vent passage junction 95.

Effects of Fluid Barrier Thickness and Clamping Force on Prevention ofFluid Barrier Breach

It can be seen in FIG. 10 that by turning screws 34 and 35 in adirection which will increase thread engagement, that an increasingamount of force can be applied to the opposite sides of fluid barriermaterial 30 by conditioning component module 11 and base module 12. Inthe preferred embodiment the combined force applied by screws 34 and 35is sufficient to overcome the opposing force resulting from the internalfluid pressure in conditioning component module 11 and base module 12plus apply approximately 2000 pounds per square inch additional clampingpressure to their surface which is in contact with the opposite sides offluid barrier material segments 103, 104, and 105. The absolute amountof clamping force applied to fluid barrier material segments 103, 104,and 105 to effect containment of sample fluids as previously describedwill depend upon the type of fluid barrier material 30 utilized and itsthickness, and the range that the temperature of the fluid barrier 30 iscycled during the course of its service life.

It is highly desirable in a sample conditioning system that its materialof construction are inert. Therefore and ideal fluid barrier material 30is a sheet of TEFLON™ plastic. It is well known in the prior art thatfluid barriers constructed from TEFLON™ plastic are susceptible toleakage due to plastic displacement, especially when its temperature iscycled through a wide range at elevated temperatures.

This is overcome in the present invention by several means. First, inthe preferred embodiment, fluid barrier material thickness is minimizedand preferably less than 0.040 inches and more preferably less than0.010 inches. By minimizing the thickness of fluid barrier material 30,compensation for its plastic displacement can be more easily effected.Although many means exist to compensate for fluid barrier material 30plastic displacement, the preferred means are by pre-loading bolts 34and 35 to produce a strain of a value equal to or exceeding the maximumpotential reduction of thickness of fluid barrier material 30 resultingfrom plastic displacement.

It has been well established by prior art that bolts may be safelytorqued to produce a stress equal to approximately 60% of the boltstensile strength. In the preferred embodiment 304 stainless steel isutilized, however, many other types of material may be used for thispurpose. The tensile strength of 304 stainless steel is approximately92,000 pounds per square inch. At 60% of this value, which is 55,200pounds per square inch, the strain is approximately 0.0018 inches perinch of free bolt length. The free bolt length is defined as the portionof bolt 34 and 35 which is not engaged in female thread. Minimizing thethickness of fluid barrier material 30, minimizes the plasticdeformation compensation requirement for fluid barrier material 30.

The minimum thickness at which fluid barrier material 30 can stilleffectively function as a fluid barrier is dependent upon the surfaceroughness of surface 92 of conditioning component module 11 and surface91 of base module 12.

Through experimentation it was found that a fluid barrier materialthickness of 0.005 inches was effective in sealing machined surfaceswith roughness of 64 micro inches. It was also empirically determinedthat when Teflon™ is the fluid barrier material 30 an initial netclamping force of 2000 pounds per square inch applied across oppositesides of fluid barrier surface is required to contain or seal withoutleakage fluids which are under a pressure of 1000 pounds per squareinch. The net clamping force is defined as the clamping force applied tothe fluid barrier material exclusive of the opposing force resultingfrom internal fluid pressure.

It was also determined that when Teflon™ is the fluid barrier material30, a net clamping force of 500 pounds per square inch applied acrossopposite sides of fluid barrier surface is required to contain or, sealwithout leakage, fluids which are at a pressure no greater than 50pounds per square inch. From this it was concluded that a minimum of 500pounds per square inch clamping force was required to effect sufficientplastic displacement of the Teflon™ fluid barrier material 30 to filland seal surface irregularities of surfaces 91 and surface 92. Clampingforces were for the most part applied and measured by means of torquegauge at ambient temperatures ranging from 70° F.-75° F.

When constructing a fluid barrier according to the invention observe thefollowing steps for selecting and forming fluid barrier material 30 andalso to select and tighten the bolts which apply the net clamping forceto both sides of fluid barrier material 30.

(a) Select a sheet of fluid barrier material 30. Preferably thethickness is approximately 0.005 inches.

(b) Shape the exterior of the selected sheet of fluid barrier material30 to conform approximately with the exterior shape of base module 12and conditioning component module 11.

(c) Form openings through the sheet of fluid barrier material 30 whichwill provide fluid communication between corresponding passages of basemodule 12 and conditioning component 11.

(d) Select the number and diameter of bolts which will supply therequired clamping force between opposite side of the fluid barriermaterial 30, when torqued to approximately 60% of the bolts tensilestrength. (

e) Select bolt lengths which will, when torqued to 60% of tensilestrength, result in a strain equal to or greater than the thickness ofthe fluid barrier material 30.

Reducing the effective fluid barrier area reduces the number and/or sizeof bolts required to produce the desired clamping force. This can beeasily done by reducing the area of the surface 91 and 92 which contactand apply clamping force to segments of fluid barrier material 30.Forming a depression of 0.010 inches to 0.015 inches in the surface of91 and 92 where contact with the fluid barrier material 30 is notdesired can be used as a means for reducing the effective fluid barriercontact area which in turn reduces the clamping force required.

As an example in FIG. 11 a surface depression 120 is formed in space 87of surface 91 and a surface depression 121 is formed in space 88 ofsurface 92. Depression 120 reduces the area of space 87 which contactssegment 105 of fluid barrier material 30 and depression 121 reduces thearea of space 88 which contacts segment 105 of fluid barrier material30.

If the bolt length 34 and 35 required to traverse conditioning componentmodule 11 is not sufficiently long to produce a strain equal to orgreater than the thickness of fluid barrier material 30 than the boltlength can be increased by use of spacers 101A and 101B as shown in FIG.12.

It has been determined that, as plastic displacement of fluid barriermaterial occurs thereby reducing bolt strain, the net clamping forcerequired on opposite sides of fluid barrier material 30 to effect fluidsealing is diminished accordingly. This is probably due to filling ofirregularities of surface 91 and 92 by fluid barrier material aspreviously mentioned.

It was found that when the fluid barrier material 30 thickness was 0.005inches and the bolt 34 and 35 lengths were at least two inches long thefirst fluid barrier around the passage junctions were not breached byfluids at pressures in excess of 1000 pounds per square inch afterextensive thermocycling from approximately 32° F. to 450° F.

Effect of Surface Geometry on Prevention of Fluid Barrier Breaching

Tests indicate that some of the major factors relating to fluid barrierblowout at high fluid pressures are the edge area of fluid barrierexposed to the fluid pressure, the plastic properties of the fluidbarrier material 30, and the friction between he fluid barrier material30 and the surfaces 91 and 92. With a given plastic material ofconstruction of the fluid barrier material fluid pressure which causesfluid barrier blowout can be significantly increased by reducing thefluid barrier thickness in order to minimize its area exposed to fluidpressure.

Testing also revealed that for a given fluid barrier material themaximum leak-free operating pressure of internal fluids could besignificantly extended by forming a slope on one or both sides incontact with he opposite sides of fluid barrier material. In FIG. 13 itcan be seen that surface segment 106 of conditioning component module 11and surface segment 107 of base module 12 are sloped. When a sufficientnet clamping force (FIG. 14) is applied between conditioning componentmodule 11 and base module 12 sloped surface 106 and 107 displace aportion of fluid barrier material 30, thereby creating a wedge shapedfluid barrier 108 sloped in opposition to the direction of the potentialinternal pressure applied by sample fluid 122 in passage grooves 81 and83 and passage junctions 93 and 94 as shown in FIG. 14. The effect ofincreasing internal fluid pressure of sample fluid 122 is the wedging offluid barrier 108 thereby creating a tighter seal. Fluid 122 may bepresent in passage grooves 81 and 83 in the event of a massive passagejunction fluid barrier failure. The forming of a wedge shaped secondfluid barrier is an additional measure of protection against samplefluid leaking to the environment.

In FIG. 15, it can be seen that a single sloped surface 106 ofconditioning component module 11 is used in conjunction with flatsurface 87 of base module 12.

After sufficient clamping force has been applied between conditioningcomponent module 11 and base module 12 to cause fluid barrier 30 toundergo plastic displacement, it can be seen that a 1/2 wedge shapedfluid barrier 113 was formed. The effect of increasing internal fluidpressure of sample fluid 122 in passage grooves 81 and 83 and passagejunctions 93 and 94 is wedging of fluid barrier 113 thereby creating atighter seal.

In the preferred embodiment the depth of the sloped surfaces 106 and 107is approximately 50% of the fluid barrier material 30 thickness and thefluid barrier material 30 thickness is less than 0.010 inches. In anycase however, it is preferred that the depth of sloped surfaces 106 and107, the depth of surfaces depressions 110 and 111, and he thickness offluid barrier material 30 in combination, after sufficient clampingforce has been applied between conditioning component module 11 and basemodule 12 to effect plastic displacement of fluid barrier 30, permitsloped surfaces 106 and 107 to make physical contact (FIG. 16).Depending on many factors such as the type and thickness of fluidbarrier material 30, the initial clamping force between conditioningcomponent module 11 and base module 12 may not result in plasticdisplacement until some period of time has elapsed.

The passage junctions between adjacent base module's in a SampleConditioning System can be prevented from leaking fluid to theenvironment and to other passage junctions in a manner similar to thatpreviously described by forming two fluid barriers and a leakcontainment passage around the passage junctions which are between aconditioning component module and base module. An example of this can beseen in FIG. 17 where passages 192A, 193A, 194A, and 195A of base module187 form junctions with corresponding passages 192B, 193B, 194B, and195B of base module 188 and opening 192C, 193C, 194C, and 195C of fluidbarrier material 189. Collection grooves 190, 191, and 192 and passages195A and 195B in concert, provide two series fluid barriers separated bya fluid collection passage in conformance with the invention and aspreviously detailed for conditioning component module 11 and base module12. Therefore, hereinafter, when base modules are assembled side by sideit must be assumed that the resulting passage junctions are renderedleak-free by the aforementioned methods.

Function and Attributes of Passages

In a manner similar to that in which corresponding vent collectionpassages 47, 70,71, 72, 73, 74 and 75 of a plurality of base modulesshown in FIG. 6 form a continuous passage 76 comprising a SampleConditioning System fluid containment network as aforementioned, othercontinuous Sample Conditioning System passages can be formed for variouspurposes. As an example in FIG. 6 passages 114A, 114B, 115A, 115B, 116A,116B, 117A, 117B, 118A, 118B, 119, and 123 comprise a passageway 124 inwhich sample fluid may flow through the desired component moduleswhereon sample conditioning occurs. Sample fluid in this example isconditioned in the manner required by the aforementioned first andsecond fluid circuits of the diagram of FIG. 3. A second example in FIG.6 are passageways 125, 126, 127, 128, 129, 130A, 130B, and 131A, and131B comprising passageway 132. In this example passages 130A, 130B,131A, and 131B provide fluid communication among the component modulesrequired by the aforementioned third fluid circuit of the diagram ofFIG. 3. Passages 125, 126, 127, 128 and 129 serve as a conduit forsample fluid flow to an external destination not shown.

A third example is shown in FIG. 6 where corresponding passages of theassembled base module comprise a forth Sample Conditioning Systempassage 133 which in a preferred embodiment may function as a fluidtransport passage for auxiliary fluids. Examples of auxiliary fluidswhich are anticipated for use in the Sample Conditioning Systemconstructed by the methods of the invention are inert fluid for purgingor cleaning the interior of the Sample Conditioning System andpressurized fluid for actuation of mechanical components such asautomated valves.

Although not shown in FIG. 6, the passage junctions between adjacentbase modules are sealed by the same method as previously described toseal passage junctions between conditioning component module 11 and basemodule 12, and between base modules 187 and 188, including the two fluidbarriers with passage grooves formed in exterior surfaces for thepurpose of collecting fluids which may breach the first fluid barrier ofa passage junction.

Sample Conditioning System passages such as passages 76, 124, 132, and133 seen in FIG. 6 formed and sealed in accordance with the methods ofthe invention are substantially better suited for transport of samplefluid within a Sample Conditioning System then the fluid transportpassages of prior art. It can be seen in FIG. 18 that prior art use ofpipe fittings in forming transport passages results in dead volume andtends to add to the overall Sample Conditioning System internal fluidvolume. It can be seen that a segment of male threads 134, with the aidof fluid barrier material 136, form a fluid seal in combination with asegment of female threads 135. The cavity 143 between male threadsegment 137 and female thread segment 138 is not in the direct path ofsample fluid 139 flowing between passages 141 and 142. The cavity 140,formed between the leading surface 145 of male pipe fitting 146 and thebottom surface 144 of female pipe fittings 147, forms a reservoir forsample fluid 139.

The trapping or removing of sample fluids by cavities 140 and 143 fromthe direct sample fluid flow paths of passages 141 and 142 is highlyundesirable. The effect of these type cavities on analytical results iswell known in the art. The inventions method of forming, joining andsealing of sample fluid passages provide minimum volume passages absentstatic fluid pocket volume. An example of this is seen in FIG. 4 wherepassages 14 and 15 are joined at passage junction 93, the passagejunction 93 performs a function similar to that of the aforementionedmale pipe fittings 146 and female pipe fittings 147. Yet the interior ofpassage junction 93 does not contain dead or unpurged cavities such ascavity 143, nor does it have and enlarged volume such as cavity 140.Passage junction 93 provides near ideal characteristics for transportingsample fluids in a Sample Conditioning System.

Assembly and Mounting of Modules to Construct a Sample ConditioningSystem

The invention also includes a method for mounting of base modules, withattached conditioning component module's, that provides for properalignment of corresponding passages in adjacent base modules, providesthe clamping force between adjacent base module to form fluid barriersaround passage junctions as aforementioned, and also provides a meansfor mounting an entire Sample Conditioning System constructed by themethods previously described.

The method consist of first constructing a mounting rail 148 as shown inFIG. 19,20,21, and 10. The mounting rail 148 slides into grooves 149 Aand 149B formed in the sides of base modules 150A, 150B, 150C, fluidbarriers 151 A, fluid barrier 151 B, fluid barrier 151C, and terminationmodules 157 and 158 as shown in FIG. 20. For sake of clarityconditioning component module were not shown mounted on base modules150A, 150B, and 150C. The mounting rail maintains alignment betweenadjacent modules and in conjunction with termination modules 157 and 158provides a method for exerting a clamping force between base modulesthereby compressing fluid barrier 151A, 151 B, and 151C as required toeffect sealing of base module and termination module passage junctions.A specific means for exerting the clamping force is shown in FIG. 20although other means are known.

In this example a first termination module 158 is retained on mountingrail 148 by pin 155 inserted through holes 153A and 153B. A secondtermination module 157 is retained on mounting rail 148 by pin 154inserted through holes 152A and 152B. A bolt 156 is threaded throughtermination module 157 with its end in contact with base module 150A. Bytightening bolt 156 a clamping force is exerted which compresses fluidbarriers 151A, 151B, and 151C as required to effect fluid sealing ofbase module and termination module passage junctions not shown, andsecures the entire assembly which includes base modules 150A, 150B, and150C fluid barriers 151A, 151B,and 151C termination modules 157 and 158and pins 154 and 155. The assembly 160 can be mounted to a mountingsurface 159 with screws 160A and 160B through holes 161A and 161B.

To remove a base module from the assembly 160, bolt 156 is loosened, pin154 is removed, and base modules are slid from the mounting rail 148.Since the base modules do not perform any sample fluid conditioningfunctions they are not likely to require removal once in service. Theconditioning component modules however can easily be removed and/orreplaced from a Sample Conditioning System assembly by loosening andremoving bolts 34 and 35 as seen in FIG. 10 and 12. It should be notedthat passages not shown, formed in termination module 158 provide fluidcommunication between the base modules and external devices throughopenings such as openings 162, 163, 164, and 165 of FIG. 20 in a mannersimilar to that described for providing fluid communication between basemodule 12 and conditioning component module 11. In a manner similar tothe method for imposing a strain in a threaded member for compensationof barrier material displacement, a strain can be imposed in themounting rail 148, by tightening bolt 156, which will compensate for thecollective displacement of all barrier material disposed between basemodules mounted on the mounting rail.

Attachment for Fluid Transport Tube The current invention also providesa means for attaching fluid transport tube to a device body such as abase module. Tubing attachments are necessary to conduct sample fluidsbetween the Sample Conditioning System and external sample fluid sourcesor disposal sites. Prior art tubing attachments are a common andfrequent source of fugitive emissions of sample fluids. The tubingattachment means of the current invention provides two fluid barriers inseries with a collection passage. A collection passage serves totransport to an external disposal site fluids which may breach a firstseries fluid barrier.

A second fluid barrier prevents fluids in the collection passage fromescaping to the surrounding environment. The function of the invention'stubing attachment and sealing method is similar to the two series fluidbarriers with collection passage previously described for sealingpassage junctions between conditioning component modules and basemodules. Multiple series fluid barriers are well known in the prior art.Examples are the compression ferrules utilized by Swagelock™, ParkersHannifin™ and Tylok™. However, the prior art does not provide means forpreventing leakage of sample fluid to the external environment bycollecting and transporting to an external disposal site fluids whichbreach a first fluid barrier.

In the preferred embodiment (FIG. 22A and 22B) a circular cavity 182 isformed in body segment 166. Body segment 166 represents a segment of thebody of any fluid containment device. The diameter of cavity 182 isreduced in four successive steps resulting in the formation of circularledges 171, 172, and 174, Fluid passage 170 is in fluid communicationwith cavity 182 between ledges 172 and 174. Female threads 176B areformed in the inner diameter of the cavity 182 between circular ledge174 and outer surface 183. A nut 168 has male threads 176A formed on itslower end. When assembly 186 is assembled as shown, lower ferrule 173rest upon ledge 172, upper ferrule 175 rests upon ledge 174, malethreads 176A of nut 168 are threaded into female threads 176B of cavity182; and tube 167 extends through the center holes of nut 168, upperferrule 175, lower ferrule 173 and rests upon ledge 171. The centerpassage 177 of tube 167 is in approximate axial alignment with passage169.

Upper ferrule 175 and lower ferrule 173 are rigidly attached and fluidlysealed to tube 167. Lower ferrule 173 and ledge 172 in combination forma first fluid barrier for sample fluid 184. Upper ferrule 175 and ledge174 in combination form a second fluid barrier in series with the firstfluid barrier. Cavity 178 and passage 170 in combination form acollection passage for sample fluid which may breach the first fluidbarrier. Nut 168 forces contact between upper ferrule 175 and ledge 174and between lower ferrule 173 and ledge 172 which in turn retains tube167 in the position shown in assembled view FIG. 22B.

In normal service passages 170 and 169 provide fluid communicationbetween body segment 166 and external fluid sources or fluid receivingsites not shown. Body segment 166 represents a segment of any devicebody which is utilized in the construction of a Sample ConditioningSystem. Should fluid contained in passages 169 and 177 breach the lowerfluid barrier it enters cavity 178 then is transported by passage 170 toan external disposal site not shown. If body segment 166 is a segment ofa conditioning component module, base module or termination modulepreviously described, then passage 170 becomes an integral part of theSample Conditioning System fluid containment network.

Another means of operating assembly 186 is to pressurize passage 170with an inert gas to a pressure equal to or slightly in excess of thefluid pressure in passages 169 and 177. A failure of the lower fluidbarrier would then result in inert gas from passage 170 flowing throughcavity 178 and into passages 169 and 177 thereby preventing sample fluidcontained in passages 169 and 177 from escaping to the surroundingatmosphere. Yet another means of operating assembly 186 is to evacuatepassage 170 and cavity 178 by external vacuum means. In the event of alower fluid barrier failure sample fluid entering cavity 178 will beconducted by passage 170 to an external disposal site not shown. Shouldthe upper fluid barrier fail then fluids from the surroundingenvironment will enter cavity 178 and be transported by passage 170 toan external disposal site not shown. In any case, however, sample fluidscannot escape to the external atmosphere. The preferred embodimentdescribed, assembly 186, achieves the desired two series fluid barriersseparated by a fluid collection passage.

While certain specific embodiments and details have been described inorder to illustrate the present invention, it will be apparent to thoseskilled in the art that many modifications can be made therein withoutdeparting from the basic concept and scope of the invention.

Further, the invention embodiments herein described are done so indetail for exemplary purposes only, and may be subject to many differentvariations in design, structure, application and operation methodology.Thus, the detailed disclosures therein should be interpreted in anillustrative, exemplary manner, and not in a limited sense.

What is claimed is:
 1. A method providing a sample fluid conditioningapparatus, comprising the steps of;(a) providing a base module, saidbase module having a fluid communication means for allowing the passageof fluid therethrough, said base module further comprising a firstdocking face having, an external surface for receiving sampleconditioning components; (b) establishing a fluid communication order ofsample conditioning components to effect conditioning of said samplefluid, comprising the steps of providing first and second sub-basemodules each of said sub-base modules further having first and seconddocking faces each said first and second docking faces having anexternal surface, said first and second sub-base modules joined at saidsecond docking face in fluid impermeable fashion so as to form said basemodule; (c) providing first and second sample conditioning components,each of said sample conditioning components having a first docking facehaving an extra surface configured to dock with said first docking faceof said base module; (d) docking said first docking face of first andsecond modular conditioning components to said first face of said basemodule, respectively; (e) providing flow of said sample fluid to saidfirst conditioning component; (g) directing said flow of said samplefluid from said first conditioning component to said fluid communicationmeans of said base module; (h) directing said flow of said sample fluidfrom said fluid communication means of said base module to said secondconditioning component.
 2. The method of claim 1, wherein there isfurther included in step "d" the additional step of docking said firstdocking face of first and second modular conditioning components to saidfirst docking face of said first and second sub-base modules,respectively.
 3. The method of claim 1 wherein in step "d" the dockingof said first docking face of first and second modular conditioningcomponents to said first face of said base module includes the step offorming a fluid communication junction, and wherein there is furtherincluded in step "d" the additional step of forming a first fluidbarrier configured to envelope said fluid communication junction.
 4. Themethod of claim 3 where there is further provided the additional step ofproviding a fluid containment passage about said first fluid barrier. 5.The method of claim 4 where there is further included the additionalstep of forming a second fluid barrier about said fluid containmentpassage.
 6. The method of claim 4 where said fluid containment passageis in fluid communication with an external fluid disposal system.
 7. Themethod of claim 6, where there is further provided, as an additionalstep, the step of forming a plurality of fluid containment conduits influid communication with said modular base.
 8. The method of claim 1,wherein there is further included in step "a" the additional step offorming a plurality of passages in said base module terminating at saidexternal surface of said base module as a passage junction, forming afirst fluid communication in step "c" there is provided the further stepof forming a plurality of passages in said first and second conditioningcomponents terminating at said external surface of said first dockingface of each of said first and second conditioning components as apassage junction, respectively, forming a second fluid communicationjunction.
 9. The method of claim of 8 wherein there is further includedthe step of forming a first fluid barrier enveloping each of the passagejunctions of said base module and said first and second conditioningcomponents, respectively.
 10. The method of claim 9 wherein there isfurther included the additional step of providing a fluid containmentpassage surrounding each first fluid barrier.
 11. The method of claim 10wherein there is further included the additional step of providing asecond fluid barrier surrounding each fluid containment passage.
 12. Themethod of claim 1 where said base module is assembled on a mounting railwhere:(a) said base module has a first slot on a first side and a secondslot on a second side and, (b) a first edge of the mounting rail engagesthe first slot of said base module and a second edge of the mountingrail engages the second slot of said base module.
 13. A method providinga sample fluid conditioning apparatus, comprising the steps of;(a)providing a base module, said base module having a fluid communicationmeans for allowing the passage of fluid therethrough, said base modulefurther comprising a first docking face having an external surface forreceiving sample conditioning components; (b) providing first and secondsub-base modules, each of said sub-base modules further having first andsecond docking faces, each said first and second docking faces having anexternal surface said first and second sub-base modules joined at saidsecond docking face in fluid impermeable fashion so as to form said basemodule; (c) establishing a fluid communication order of sampleconditioning components to effect conditioning of said sample fluid; (d)providing first and second sample conditioning components, each of saidsample conditioning components having a first docking face configured todock with said first docking face of said base module, said first andsecond sample conditioning components each further having a seconddocking face having an external surface; (e) assembling said sampleconditioning components to said base module in a fashion which providesconveyance of said sample fluid between adjacent sample conditioningmodules; (f) docking said first docking face of said first and secondconditioning components to said first face of said base module,respectively, while docking said second face of said first sampleconditioning component to said second face of said second sampleconditioning component, forming first and second fluid conveyancejunctions, respectively; (g) providing flow of said sample fluid to saidfirst conditioning component from said base module via said first fluidconveyance junction; (h) directing said flow of said sample fluid fromsaid first conditioning component to said second conditioning componentvia said second fluid conveyance junction.
 14. The method of claim 13,wherein there is further included in step "d" the additional step ofdocking said first docking face of first and second modular conditioningcomponents to said first docking face of said first and second sub-basemodules, respectively.
 15. The method of claim 13 wherein in step "d"the docking of said first docking face of first and second modularconditioning components to said first face of said base module includesthe step of forming a fluid communication junction, and wherein there isfurther included in step "d" the additional step of forming a firstfluid barrier configured to envelope said fluid communication junction.16. The method of claim 15 where a there is further provided theadditional step of providing a fluid containment passage about saidfirst fluid barrier.
 17. The method of claim 16 where there is furtherincluded the additional step of forming a second fluid barrier aboutsaid fluid containment passage.
 18. The method of claim 16 where saidfluid containment passage is in fluid communication with an externalfluid disposal system.
 19. The method of claim 18, where there isfurther provided, as an additional step, the step of forming a pluralityof fluid containment conduits in fluid communication with said modularbase.
 20. The method of claim 13, wherein there is further included instep "a" the additional step of forming a plurality of passages in saidbase module terminating at said external surface of said base module asa passage junction, forming a first fluid communication junction, andwherein in step "d" there is provided the further step of forming aplurality of passages in said first and second conditioning components,terminating at said external surface of said first and second dockingface of each of said first and second conditioning components as passagejunctions, respectively, forming second and third fluid communicationjunctions.
 21. The method of claim of 20 wherein there is furtherincluded the step of forming a first fluid barrier enveloping each ofsaid passage junctions of said base module and said first and secondconditioning components, respectively.
 22. The method of claim 21wherein there is further included the additional step of providing afluid containment passage surrounding each first fluid barrier.
 23. Themethod of claim 22 wherein there is further included the additional stepof providing a second fluid barrier surrounding each fluid containmentpassage.